Thermal protection sheath and its fabrication method

Abstract

A heat-reflective protective sleeve includes a substrate ( 10 ) and a sheet of reflective material ( 20 ) fixed on the substrate ( 10 ). The substrate ( 10 ) is elastically deformable from a non-operating position and the sheet ( 20 ) is pleated on the substrate ( 10 ) in the non-operating position.

1. A thermal protection sheath, comprising:
 an inner tubular substrate that has an exterior surface with a plurality of recesses therein, said substrate being longitudinally and radially elastically deformable between a relaxed configuration and an expanded configuration in which a length or a radius of said substrate is larger than in said relaxed configuration; and  
 a reflective foil fixed to said substrate and contacting said exterior surface only intermittently so as to form air pockets, said reflective foil being arranged on said substrate to have a plurality of indentations that correspond to said plurality of recesses when said substrate is in said relaxed configuration and that disappear when said substrate is elastically deformed from said relaxed configuration to said expanded configuration.  
 
     
     
       2. The sheath of  claim 1 , wherein said substrate comprises a corrugated tube and said recesses are annular depressions in said exterior surface, and wherein said air pockets are in said annular depressions between said foil and said corrugated tube. 
     
     
       3. The sheath of  claim 1 , wherein said substrate comprises a woven material and said recesses are between threads of said woven material.